Mercury-vapor rectifier and the like.



J. JONAS.

MERCURY VAPOR RECTIFIER AND THE LIKE.

APPLICATION FILED o cr. I. I914.

1,153,794. Patented Sept. 14, 1915 2 SHEETSSHEET l.

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l. JONAS. MERCURY VAPOR RECTIFIER AND THE LIKE.

' APPLICATION FILED OCT. 1. I914.

1,153,794. Patented Sept. 14, 1915.

- 2 $HEETSSHEET 2 WITNESSES, MJW,

UNITED STATES PATENT OFFICE.

JULIUS JONAS, or BADEN, SWITZERLAND, AssIGNoR'To AKTIENGESELLSCHAFTBROWN, IBOVERI & CIE.,0F BADEN, SWITZERLAND.

MERCURY-VAPOR RECTIFIER AND THE LIKE.

Specificationof Letters Patent.

Patented Sept. 14, 1915.

Application filed October 1,-1914. Serial No. 864,470.

Improvements in and Relating to Mercury Vapor Rectifiers and the like,of which the following is a specification.

This invention relates to the working of mercury vapor rectifiers andthe like (it may be in parallel) by means of a common transformer. 7

In the accompanying drawings: Figure 1 illustrates diagrammatically ascheme of transformer winding such as is applicable to the presentinvention. Fig. 2 is a diagram of connections between such a transformerand two mercury rectifiers, as exemplified by the prior art. Fig. '3illustrates diagrammatically one way of carrying the present inventioninto effect by means "of a single phase transformer feeding tworectifiers. Fig. 4 is a similar view showing the use of a singlephasetransformer feeding three rectifiers'and abattery, and Fig. 5 astill further view showing a polyphase transformer feed ing threerectifiers.

It is a known thing to feed mercury vapor rectifiers which can workinparallel. on a common direct current system, from special secondarywindings of a common transformer, but it is often found in that casethat the output is not uniformly distributed over the severalrectifiers. The reason of this phenomenon is explained with reference toFigs. 1 and 2 which show respectively the scheme of a transformerwinding and a diagram of connections between such a trans former and twomercury rectifiers.

In Fig. 1 there is represented the common .single-phase transformer t,on the two cores I and II of which there are the primary windings m, a"and the two secondary Jwindin'g's b, b" and 0', c. 0; is wellinterlinked with b', and 0 and so is a" with b and 0". Interlinking of awith b" ando", and a with b and 0 is not so good because the coils arewound on different core members.

If the two rectifiers g and g, are connected up to the secondarywindings of the transformer in the manner shown in Fig. 2, good workingof these rectifiers is not possible. On the one hand the transformerwill show a big voltage drop (owing to great leakage) and on the otherhand the distribution of the output over the two rectifiers will beunequal if in their circuits differences in themselves unimportantexist. If in fact we take into account that at any moment, of the twoanodes of each rectifier, only one is conducting current, it will beperceived that of the four windings b, b, c, c in each moment, only twoare conducting current,

while the other two are without current. These windingsinterchange thepart they play in each following half period of the alternating current.In F i g. 2 the windings Z), c, are conducting current and only wellinterlinked with a. As, however, the primary current of the transformerflows through a and a" in series a considerable stray flux will resultowing to the bad inter-linking of the secondary windings b, c

with a, and will entail a considerable drop 'of voltage in thetransformer.

On this scheme of connections furthermore, the secondary current maydistribute itself quite differently over the windings b and c, becauseeven slight differences in the rectifiers will destroy the symmetry ofthe parallel branches carrying current.

The object of the present invention is to provide for feeding mercuryvapor rectifiers or the like from separate secondary windings of acommon transformer (and .where necessary working in parallel) withoutthe above disadvantages.

The invention consists 1n so connecting up the anodes to the secondarywindings that those parts of the secondary windings which simultaneouslycarry current, are in their entirety uniformly distributed over thewhole primary winding.

i It is to be understood that the windings of the scheme shown in Fig. 3are disposed upon the core members in a manner similar to thatillustrated in Fig. 1. These windings are connected as indicated .in thediagram in Fig. 3.

In Fig. 3 the windings I), b" on the one hand and 0', c on the other areconnected up to the simultaneously working anodes of the two rectifiersg and 9 so that b and 6''- simultaneously carry current during'the onehalf period and c and 0" during the following half period. The windingsb and b" are well interlinked with a and a as also are c and c with aand a", so that the transformer shows only a very small voltage drop.Further, owing to the good interlinkage, the current in b will stand ina [fixed ratio to that in b" determined by the by the ratio of the turnsof these winding parts.

In Fig. 4; the primary windings a, a";

a are provided with secondary windings b, b", 6' and c, c", 0". Now 6 isconnected with c, b" with'c', b' with c, toform the three secondarywindings, b, c; b, 0" and b', 0. These connections between the severalsections of the three secondaries noted are interlinked by a connectingwire which is conducted to one pole of a battery 8. Thefree end of b isconnected with the anode e that of b" with 6 that of 6" with 6 and thefree end of c with 6 that of 0 with. 6 and that of 0' with e Thecathodes 7a,, 70 and k, are connected by a common conductor Z to theother poleof the battery. As will be perceived from the direction of thearrow which indicates the flow of current in one half period, thewindings b, b"

and b' .are simultaneously traversed by current and in the other halfperiod 0', 0"

all.

In Fig. 5, the three rectifiers g g and g, are provided with three pairsof terminals, each pair being connected with certain parts of thewindings of one phase. Electrodes e e are joined to b, and e e, and e,are joined to b," and 0 e and e, are joined to b and 0 This completesthe connections as regards one phase. As to another phase electrodes i2', are joined respectively to 6 0 a, and a, to b. and 0 i and 2', to 6and Q7 As to the third phase the electrodes 72,, 7),, are connected tob, and 0 29 nto 1)," and 0 and p and p, to 6 and 0 The secondarywindings connected with the anodes of one rectifier are in starconnection and the star points thus resulting are connectedswith eachother and form the negative pole of the'direct current system, .the'positive pole of which is represented by the connecting conductor Z ofthe three cath- "ondary windings, superposed on a primary winding, acommon connection between each secondary section and each cathodec1rcu1t and connections between each secondary section and an anodecircuit whereby the active anodes are fed from secondary sections,energized throughout their length by a primary portion having the sameaxis of magnetization.

2. A system of rectification comprisinga polyphase transformer,rectifier elements provided with cathodes and anodes, corresponding innumber with the polyphase supply, a plurality of sectionalizedsecondaries superposed on each primary phase of the transformer, commonconnections between each secondary section of each phase and therectifier cathodes and connections between-the other ends of thesecondary sections of each phase and the rectifier anodes, whereby eachactive anode is fed ,from a secondary section energized throughout itslength bya primary portion having the same axis of magnetization.

In testimony whereof, have 'afiixed my signature in presence of twowitnesses.

CARL CULvsnN, WILLIAM W. JOHNSTON.

